It is frequently necessary to laminate together different materials to form complexly shaped articles of manufacture. For instance interior body parts constituting, for instance, the dashboard or door panels of an automotive vehicle have an outer skin layer formed by a durable leatherlike foil, an intermediate layer of a soft foam, and an inner skin.
As described in U.S. Pat. No. 4,873,045 of Fujita (British equivalent 2,206,835 published 15 Jan. 1989) this can be done by extruding a layer of synthetic-resin foam and depositing it immediately on a lower die half. A two-part laminate having the outer skin and an intermediate blocking layer is secured to the lower surface of an upper die half which is then pressed down over the foam layer on the lower die. This deforms both the foam layer to conform to the upper face of the lower die and the upper laminate to conform to the lower face of the upper die, simultaneously bonding the two layers together.
Such a process does not allow the lower surface of the base body to be highly contoured. In addition the base body must be of substantially uniform thickness. Thus it is impossible to provide integral attachment rivets or the like on the base body. Furthermore this arrangement frequently presses the base body in many locations, in particular where it is formed with a high bump or low recess, to excessive thinness, leaving the finished article less cushioned in these regions.
It is also known, for example from U.S. Pat. No. 4,501,714 of Strobel and European patent 197,496 of Ongena (based on U.S. Ser. No. 07/718,913) to put decorative foils or the like on one surface of a mold so that when the mold is closed this decoration will be integrally bonded to the material with which the mold is filled. Such a procedure can only be used for limited surface decoration and is fairly complex.
PCT application 83/02747 (based on U.S. Ser. No. 07/345,938) describes a coextrusion method where a laminate foil is subsequently separated into several parts between the layers. Another laminate extrusion system is described in German 3,141,410 of Troedsson. Various extrusion/molding systems are further described in German patent 3,144,084 of Oelsch, German patent document 1,729,629 filed 27 Sep. 1967, and in Austrian patent 263,346 of Hey. The in-house publication "Zweifarben-Spritzgie.beta.en" (Two-color injection molding) of ARBUPG describes a system for coinjection-molding two resins of different colors. None of these arrangements allows a highly contoured base element to be laminated with a uniform-thickness skin.